1. Field of the Invention
The present invention relates to marine anchors.
2. Description of the Prior Art
The basic requirement of a marine anchor is an ability to dig into a mooring bed when pulled forwardly, and to stay stable in the penetrated attitude in the bed as it is pulled further. It is also well established that for high holding power the anchor should be relatively deeply buried during anchor setting. It will be appreciated that the nature of mooring beds varies considerably, for example, from hard soils of granular noncohesive dense gravels and sands; cohesive stiff clays to soft soils of cohesive muds. In some instances the mooring bed may be rocky whereupon the anchor must be able to hook vigorously onto a rock to achieve mooring. Satisfactory operation of an anchor in a particular mooring bed has required the anchor to have a particular geometry including a fluke angle compatible with the mooring bed soil. The fluke angle is the angle formed between the fluke and a line in a fore-and-aft plane of symmetry of the anchor extending between the rear of the fluke and an anchor line attachment point in the forward end of the shank.
An object of the present invention is to provide an improved marine anchor which self-orientates to a ground-engaging attitude when cast in an inverted position on and pulled horizontally over a mooring bed surface. Also continues down by leveling itself with the gradient density.
The present invention pertains to a marine anchor which is symmetrical about a fore-and-aft plane including a basic anchor structure. The anchor has an arcuate shank which has a first end and a second end. The main portion of the anchor is constructed of arcuate triangular shaped flukes which are integral and terminate in a forwardly extending point. The point constitutes the digging end. The shank extends perpendicularly upwardly and forwardly from said flukes. The second or upper end of the shank terminates in an anchor line attachment means. The termination of the upwardly and forwardly extending shank extends substantially beyond the point defined by the flukes. The first end of the shank is affixed to the flukes at a point rearwardly from the forwardly extending point at substantially aft of a mid-point of the flukes.
The flukes together define an approximate delta shaped configuration and defines a longitudinal configuration with the end of the shank at the bottom of the arc and the flukes curving upwardly about the shank. The flukes terminate rearwardly in a substantially horizontally disposed arcuate trailing edge. Each fluke has a wedge shaped cut-out resulting in an outer portion of each fluke having a flap-member. The flap-like member or fin is turned downwardly extending the view that it resembles a flap. The flap gives the ability of the anchor to achieve horizontal travel as it is pulled through a mooring bottom.
The arcuate trailing edge assists in preventing the anchor from lying on its back. It has been found that the shank should extend upwardly for a sufficient height to keep the anchor from lying on its back and low enough to be able to turn right side up when the anchor starts from a point of lying on its side.